Prefabrication of Structural Components for Medium-Span Roofs: Italian Manufacturing of the Hyperbolit Silberkuhl System (HPV)

This work is part of a research project conducted by the author on industrial construction in Italy between the 1950s and 1970s. It refers to the contribution made to construction history by building companies through the study of the methods they used. In particular, it explores the topic of so called ‘medium-span roofs’ for factories (within 20 m). Starting from the years of the so-called ‘Italian economic miracle’, factory construction intensified in a large part of the country. Compared to the years preceding the Second World War, this type of building had evolved. The main experiments focused on solutions aimed at limiting the use of columns; consequently, the roof span increased. Construction of particularly prestigious factories – influenced by the so-called Milanese structural design – also pertains to this topic. This study focuses on a serial construction method for industrial building roofs. It was patented by engineer Wilhelm Johannes Silberkuhl in Germany (the Hyperbolit Silberkuhl system, HPV) and it was used by Sogene (the construction company of Società Generale Immobiliare, SGI) for construction of some factories in Italy during the 1960s. The HPV method was based on prefabricated concrete thin vaults with double curvatures: particular geometry and prestressed reinforcement allowed creation of light elements, easy to transport and to assemble. Moreover, this study provides a further contribution to a reconstruction of Sogene's overall enterprises, a construction company particularly involved in industrialization processes in the construction field. Bibliography, technical magazines and original archive sources are taken as a reference.